The current source for many chemicals and materials is petroleum. Nearly $24 billion (US) worth of hydrocarbon feedstock is used annually in the chemical industry (Gavrilescu and Chisti, 2005). Anticipation of its limited future availability, along with record high prices has spurred interest in alternatives that will be both sustainable and cost-effective. Hopeful visionaries have already started to talk about a “carbohydrate economy” replacing the old “hydrocarbon economy”. It has been stated that carbohydrates are the “sleeping giant” of biotechnology and that carbohydrates will be the next century's feedstock alternative to petroleum-based products (Frazzetto, 2003). Using carbohydrate feedstock offers the possibility of creating biodegradable and thus environmentally friendly products, as well as providing a sustainable resource for the feedstock.
Maple sap is a naturally occurring, unprocessed crystal clear liquid, having the constituency and clarity of water, which derives from sugar-maple trees. It is a sweet and pure solution containing between 1 and 3% sugars mostly sucrose, traces of glucose and fructose, nitrogenous and phenolic compounds, organic acids as well as different minerals (Morselli and Whalen, 1996). Maple sap is one of the abundant and renewable sources of sugars, available in relatively large quantities in eastern Canada, particularly in Quebec ((Whitney and Upmeyer, 2004). The transformation of maple sap has traditionally been geared towards the production of maple syrup, the most important non-timber forest product in Canada. Over the last five years, Canada has accounted for 84% of the world's production of maple syrup, with the province of Quebec accounting for 92.9% of domestic production. However, the long-term economic survival of this industry in Quebec is being threatened by the year-over-year accumulation of inventory surpluses due to an imbalance between supply and demand of maple syrup products. According to the Quebec maple syrup producer's federation, the volume of bulk inventories accumulated in Quebec since 1999, before the 2005 harvest, was 60 million pounds (Agriculture and Agri-Food Canada, 2005). These figures suggest the immediate need to manage maple syrup surpluses and one alternative is developing new value added industrial applications by different biotechnological processes.
Apart from maple syrup and its co-products, little work has apparently been dedicated to the use of maple sap as a renewable feedstock for the chemical and material industries. Woodward and Orr (1998) showed that maple sap has the potential to be converted into hydrogen using enzymes, and Morin et al. (1995) used low grade maple sap as a raw material for exopolysaccharide production by Enterobacter agglomeran. 
Recently, biodegradable plastics such as polyhydroxyalkanolates (PHAs), for example poly-β-hydroxybutyrate (PHB), have received increased attention because of their thermoplastic or elastomeric properties resembling those of petroleum-based plastics, yet are completely biodegradable (Steinbuchel et al., 1992). It is known that Alcaligenes and other bacteria can produce polyhydroxyalkanolates from pure sugar feedstocks. In addition to being produced biologically, these alternative polymeric materials are capable of being converted to relatively harmless degradation products, CO2 and H2O, through natural microbiological mineralization (Braunegg et al., 2004). To date such biotechnologically produced commercial polyesters have been from refined raw materials such as sugar cane and molasses in Brazil, sugar beets in Europe and corn in the United States. Such processes suffer from a number of disadvantages, including the need to refine the raw materials.
There is a need in the art for a more cost-effective process for the production of poly-β-hydroxybutyrate from unrefined raw materials.